Recently a group of scientists discovered florescent coral at a depth of about 160 feet (50 meters) in the Red Sea. What is surprising about this, you may wonder.
Although there have been discoveries of fluorescent corals in shallower areas of the reef, this is the first time that fluorescent coral reefs have been discovered in deep water.
It has scientists excited about the possibilities of using fluorescence in other areas such as medical research.
What Is Fluorescence?
Have you ever heard of invisible ink? You may have seen it in movies, where words on a paper are illuminated by light.
As magical as this seems, the change in color is due to science. The ink is absorbing higher energy light and emitting lower energy light. This reaction is an example of fluorescence. Let's understand a bit more about light first.
Light is a very broad term that describes a spectrum of Electromagnetic Rays, including Gamma Rays, Infrared Light, and Ultraviolet Light. One part of the Electromagnetic Spectrum is Visible Light or the colors that we can see with the human eye. These rays travel in curvy lines, and each type of ray is characterized by a different wave pattern. For example, Gamma Rays have a shorter wavelength than Infrared Light. A shorter wavelength is associated with higher energy, so Gamma Rays also have more energy than Infrared Light.
But What About Fluorescent Corals?
Corals are animals that live underwater. They grow in colonies called reefs, which are formed by thousands of small corals clinging on to rocks. The Great Barrier Reef in Australia and the New Caledonia Barrier Reef in Caledonia—also near Australia—are examples of major coral reefs in the world.
What makes the corals in the Red Sea fluoresce? Scientists have shown that fluorescent objects absorb higher energy (or shorter wavelength) light and emit lower energy (or higher wavelength light). Since the corals of the Red Sea are deep in the water where there is very little visible light, scientists theorize that these corals absorb ultraviolet light and emit visible light. They have special pigments called photoproteins, which enable them to convert invisible light to visible light.
Fluorescence is not just used to create pretty colors; corals have evolved photoproteins for a biological reason. The visible light is used by algae—which are eaten by the coral—to make food through photosynthesis.
It turns out that the optical properties of these photoproteins could be used for biomedical research. They can highlight cells and cell structures under a microscope. For example, they can help track cancer cells and screen for new cures.
Isn't it fascinating that a simple organism that we don’t think very much of is not only majestic but could also have so many potential uses in medical research!